Campbell MetSENS Series - Acknowledge Active Command (A!); Send Identification Command (Al!)

Table B-1: Campbell Scientific sensor SDI-12 command and response sets
Name
1
Command Response
Address query
?!
a<CR><LF>
Change address
aAb!
b<CR><LF>
Start measurement
aM!
aM1!...aM9!
atttn<CR><LF>
Start measurement
and request CRC
aMC!
aMC1!...aMC9!
atttn <CR><LF>
Start concurrent measurement
aC!
aC1!...aC9!
atttnn<CR><LF>
Startconcurrentmeasurement
and request CRC
aCC!
aCC1!...aCC9!
atttnn<CR><LF>
Send data
aD0!...aD9!
a<values><CR><LF> or
a<values><CRC><CR><LF>
Continuous measurement
aR0!...aR9!
a<values><CR><LF>
Continuous measurement
and request CRC
aRC0!...aRC9!
a<values><CRC><CR><LF>
1
Information on each of these commands is given in the following sections.
B.1.1 Acknowledge active command (a!)
The acknowledge active command (a!) is used to test a sensor on the SDI-12 bus. An active
sensor responds with its address.
B.1.2 Send identification command (al!)
Sensor identifiers are requested by issuing command aI!. The reply is defined by the sensor
manufacturer but usually includes the sensor address, SDI-12 version, manufacturer’s name, and
sensor model information. Serial number or other sensor specific information may also be
included. Source: SDI-12: A Serial-Digital Interface Standard for Microprocessor-Based Sensors
(see References [p. 1]).
Command: aI!
Response: allccccccccmmmmmmvvvxxx...xx<CR><LF>
Where
a = sensor address
MetSENS-Series Compact Weather Sensors 26